Redmine/app/views/watchers/_new.html.erb

<h3 class="title"><%= l(:permission_add_issue_watchers) %></h3>

<%= form_tag({:controller => 'watchers',
              :action => (watched ? 'create' : 'append'),
              :object_type => watched.class.name.underscore,
              :object_id => watched},
             :remote => true,
             :method => :post,
             :id => 'new-watcher-form') do %>

  <p><%= label_tag 'user_search', l(:label_user_search) %><%= text_field_tag 'user_search', nil %></p>
  <%= javascript_tag "observeSearchfield('user_search', 'users_for_watcher', '#{ escape_javascript url_for(:controller => 'watchers',
                 :action => 'autocomplete_for_user',
                 :object_type => watched.class.name.underscore,
                 :object_id => watched) }')" %>

  <div id="users_for_watcher">
    <%= principals_check_box_tags 'watcher[user_ids][]', (watched ? watched.addable_watcher_users : User.active.all(:limit => 100)) %>
  </div>

  <p class="buttons">
    <%= submit_tag l(:button_add), :name => nil, :onclick => "hideModal(this);" %>
    <%= submit_tag l(:button_cancel), :name => nil, :onclick => "hideModal(this);", :type => 'button' %>
  </p>
<% end %>